Question
10 years ago age of A is as old B 6 years ago and Age of
C after 7 years is 20 years. If present average age of them is 25 years, then find the sum of the ages of A and C, 3 years ago?Solution
Let present age of A = a, B = b, C = c According to question, => a - 10 = b - 6 => b = a - 4 Age of C after 7 years, => c + 7 = 20 Present age of C = 20 - 7 = 13 Total age of them = 25 × 3 = 75 years Now, a + (a - 4) + 13 = 75 => 2a - 4 = 62 => a = 33 years Required sum = (33 - 3) + (13 - 3) = 40 years
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